message encodeing

hmmm sounds more intellectually interesting than visually interesting - which would put it in the category of "not what Discovery is looking for." though an overview of encoding methods would be interesting as a program in its own right.

Not unexpected responses, I wasn't expecting the idea to be just rubber stamped I had the idea the other day and if it can be turned into something useful why not.

As to SOME electronic keypads: At our Condo, some owners made the mistake of installing keypad entry on their garages. Unfortunately, since our community is not a 'gated' community, thieves were able to walk up to these garages, break off the keypad itself, and then just cross the main wires. And, viola! The garage apparently opened and they took whatever it was they wanted to take.

Not really breaking the code, as it were --- BUT, it might make for a humorous moment during such an episode -

"Here's a keypad entry system placed on a storage unit, protecting the contents inside. Let's see if anyone can come up with the proper code to compromise the security system. It's said that these are very, very hard to decode..."

(Someone walks up, breaks the box, crosses the wires and opens the unit)

"Ah, yes. And then there's that!"



However, I am a little back and forth if we'd be teaching future crooks the weaknesses of certain keypad systems, or if we'd be teaching home owners not to use some keypad systems, and therefore saving their skins?!

Maybe better not to cross that bridge.

First of all, you should read the book "Colossus: The secrets of Bletchley Park's code-breaking computers" if you want to know what really happened in Bletchley Park. There is still a lot of false information around about the Colossi "Computers". Those were not designed to be what we would call a computer nowadays, they just contained technology you could make a decent computer out of it! All they really did was counting 1's and 0's for statistical analysis of encrypted messages.

You can't "just decode something" at all! You need to know how it was encrypted and the proper key. If you don't even know what the symbols are for, you can't decode it at all.

For Enigma messages, the outcome is a human readable text in a known language so you look for patterns in the encrypted message and fiddle around with various combinations of decryption to figure out the key. Statistical analysis tells you if your result gets "better" or "worse" so you don't have to try all possibilities (brute force) here. In fact, the pre-war Enigma can be broken by pen and paper in a matter of minutes, the military version just has an additional wheel connected in series and two new different wired wheels along with the "Steckerbrett" for real randomness in the key.
The real Problem for the Allied was the Lorenz "Verschlüsselungszusatz" for Teletype machines. This was the main method of communication for the 3th Reich and this was kept a secret until a few years ago since the Colossus which was the only good method to break this code was kept a big secret until a few years ago.

You really need time to read the first chapters where they explain how they did it.

But unfortunately there is a lot of information missing you need to fully understand the tricks. You might want to learn about Teletypes and the CCITT-2 (Murray) code first before you read the book. For example, a Teletype uses 5-bit for everything but the alphabet is sorted to save "machine movements" like the morse code. Not for speed but to safe wear on the machine. This makes bit 3 and 4 rather rarely used for text messages and one of the Geniuses just looked at those to analyse the pattern of encryption since the plain code would have mostly zeros there.

The headquarters mainly used encrypted Teletypes over landlines for secure messages. But since there were not enough telephone lines left intact in the areas of fight, they used standard Teletype machines to record the encrypted message on PPT (punched paper tape) and then fed them into Teletypes connected to a radio for "the last miles". The receiver then has a machine which decodes the message, either fed by the radio, landline (if available) or by PPT (delivered by a messenger or from a machine in the same building with outside access).
Since the occupied territory grew very quickly and the retreating enemy forces destroyed telecommunication systems and especially telephone lines, a lot of the message traffic had to be done by radio. The Germans used directional antennas and as little transmitter power as possible so the radio links had to be pretty secure they had thought. But the nature of the Teletype system still required a pretty strong signal in order to work reliable and the British intelligence service had excellent directional antennae and real sensitive gear and could pick up a lot of those radio links they did copy on iron wire recorders.

The Enigma machine was used for mobile applications, soldiers and command posts in the field and the submarines.

The key to break the so called "Tunny machine" (Lorenz Verschlüsselungszusatz) was intercepting messages which were sent through both systems. So they broke the weak Enigma code and had a plain text they tried to make use of on Tunny messages the very same length which were sent on the same day. That's how they were able to discover the very last secrets of the Tunny machine.

What had also helped a lot was that some lazy German operators had sent their keys in plain text over radio links during the first year of the war. This was sort of OK since the Allies had no clue how the encrypting system works but once they had a good idea how the system works, the old recorded messages were a superb playground to figure out the details!

Wasn't/isn't the standard practice to write your message, then encode it (even if into a 'shorthand' version) and then to send it through the machines?

By the way, what makes breaking Enigma codes easier is the fact that a "space" is always a space - the machine has no space key. So you can tell the length of words all the time. In the English language, you can spot "I" and "a" pretty easily but also the German language has lots of words which are often used and have a relative unique length. Especially since you can always see when there is a new sentence and you can guess plenty of words from the header. For example, the submariners had to send a weather report regularly which always starts with "WETTERBERICHT:" which tells you the kind and setting of the first encryption drum.

The Tunny machine also encrypts all other characters (Especially Space) which makes it real hard to guess anything written in the message.

Here's a video:



On the top of the machine is the PPT reader, beneath it is the printer and PPT writer.

You can send a PPT, you can write a PPT - individual or at the same time, you can run the message from the PPT through a encryption machine and print the result as PPT or human readable paper. You can also run a PPT through the reader and add something using the keyboard or skip parts of the PPT. You can copy several short PPT stripes to a long stripe.